On Wednesday, March 27, 2013, growers, scientists, and grape enthusiasts met online for a National Clean Plant Network for Grapes (NCPN-Grapes) Special Webinar on Grapevine Red Blotch. Tim Martinson, Senior Extension Associate at Cornell University, organized and moderated the event which had 430 registrants when registration closed on Monday, March 25.

The webinar consisted of three presentations, each followed by a brief question and answer period.

Marc Fuchs, Grapevine Virologist at Cornell University, started the webinar with a presentation on GRBaV, its association with Red Blotch disease and presence in vineyards. With contributions from Mysore Sudarshana and Keith Perry, he was able to provide information on how the virus was discovered and the classification of the virus.

Rhonda Smith, University of California Cooperative Extension Farm Advisor for Sonoma County, followed Fuchs, presenting An Extension Perspective: Field observations and impact on vines. Smith provided examples from the field and pictures showing various expressions of the symptoms, which may be linked to how different varieties are affected.

Deborah Golino, Director of Foundation Plant Services at UC Davis, concluded the webinar with her presentation on Testing and identification of vines and planting material. Golino provided information on the testing results of both the FPS Classic and Russell Ranch Foundation blocks, as well as information about the National Clean Plant Network and the 2010 protocol.

After each presentation, Martinson chose a few questions from the chat bar to ask the presenters. Questions from the chat bar were also answered throughout the talks by other experts on the panel, including Sudarshana and Perry, along with Keith Striegler from the National Clean Plant Network. Any questions that were not answered during the webinar have since been answered and are included on a PDF transcript posted here.

Not only is the transcript available, but Martinson and his team recorded and posted the webinar in two formats. You can watch the Webex version here, please note that this version requires Java but has much higher quality audio. Or you can view the YouTube version:

Grapevine Red Blotch associate Virus (GRBaV) is a newly discovered virus associated with red blotchy leaves and lower brix. For more information on the virus and symptoms, please visit the Integrated Viticulture website or look at previous blog entries here and here. More information on the webinar, including links to the recordings and chat bar responses, can be found here.